Computer keyboard operators face several problems, especially when involved in high production work. The operation of a computer keyboard for an extended period of time causes physical loading of the operator's neck and upper extremities. Similar problems are experienced by operators of conventional typewriters and other devices including key pads.
There is an abundance of data demonstrating that the human body uses many anti-gravity muscles in the hands, arms, shoulder girdle, neck and back during the operation of computer keyboards. Most of these muscles must remain contracted to keep the hands in position over the computer keyboard. Other muscles move the hands over the keyboard. As a result, many muscles get little rest during repetitive and continuous keying operations. Little benefit is obtained when the operator is not keying, for example, when the operator is waiting for a command to be processed by the computer. During this period, the hands may still be rigidly held above the keyboard and/or the wrists may rest on an edge of the keyboard. In the latter case, muscles in the arms and upper extremities may still be contracted. This situation creates many barriers to productive work, including: the requirement of frequent rest periods for tired muscles; the deterioration of correct keying technique over a work period; the development of overuse and repetitive motion injuries to hands, wrists (especially in the Median Nerve and Carpal Tunnel region), elbows, shoulders and neck; and the overloading of the shoulder, scapular and cervical regions (muscles, tendons and nerves) by the continuous weight of the upper extremities.
The demanding use of computers has created a two-fold problem related to arm support and mobility during keying operations. Existing keyboard hand rest devices assist an operator by providing a stationary resting board adjacent the keyboard. Such boards are essentially flat or curved planes supporting the wrist in a static rest position when keying is terminated. Such stationary supports are not effective when the operator is typing; there is no design feature to permit rapid movement over the complete keyboard while the wrists or forearms are at rest. The stationary hand rest devices do not address the functional requirements for easy movement of the hands over the keyboard in high speed operation.